Device and method for handling tubular knitted articles, such as stockings and socks or the like

ABSTRACT

Disclosed is a device for handling tubular knitted articles having a first end and a second end, comprising in combination: a first pick-up member and a second pick-up member ( 51 A,  51 B) for the tubular articles, which can be actuated alternatively to engage one end of the tubular articles; detection means to determine the orientation of the first and of the second end of the tubular article and a control unit. The two pick-up members are controlled to alternatively engage the tubular article according to the orientation of the tubular article detected by said detection means.

TECHNICAL FIELD

The present invention relates to methods and devices for handling tubular knitted articles, in particular, although not exclusively, stockings and socks.

More specifically, the present invention relates to methods and devices which have the function of correctly orienting tubular articles picked up from a container in which they are placed randomly.

STATE OF THE ART

To produce stockings and socks, semi-finished tubular knitted articles are usually produced by either single or double cylinder circular knitting machines. The semi-finished article delivered from the circular machine has an elastic band at one end and an open toe at the opposite end. The open toe must be sewn or linked to form the closed toe of the finished tubular article. In some machines closing of the toe is performed using devices combined with the needles of the cylinder and/or of the dial of the machine. Nonetheless, this requires a specifically designed knitting machine, or a modification to existing machines.

When, on the other hand, the semi-finished articles are unloaded from the circular machine with the toe still open, a subsequent processing operation is required on each article, which consists of picking up the article and inserting it with the correct end, i.e. the end forming the open toe, into a linking or sewing machine. These operations to pick up the tubular articles, which have been placed randomly in a container, and position them on a tubular transport member or directly in the sewing or linking machine are conventionally performed by hand, resulting in labor costs having a high incidence on the finished product.

Machines have also been designed to allow these operations to be performed automatically.

For example, U.S. Pat. No. 5,040,475 describes complex machinery that picks up individual tubular articles from a container in which they have been placed randomly. By feeding the article along a specific processing path, detection means first detect the orientation of the tubular article along the feed path, recognizing whether the toe or the elastic band of the article is the leading end. After this has been detected, the tubular article is placed in an intermediate station, from which it is delivered in one direction or in the opposite direction according to the orientation with which it entered the station.

Therefore, when exiting the intermediate station the tubular article is always facing in the same direction (i.e. always with the toe being the leading end, or always with the elastic band being the leading end) to be then spread longitudinally and inserted over a transport tube which transfers the tubular article towards a sewing machine. This machinery is extremely complex and not very reliable.

JP-A-7468502 and JP-A-1272801 describe other appliances for handling tubular articles such as stockings or socks for the purpose of suitable orientation thereof.

U.S. Pat. No. 6,719,577 describes a device, which longitudinally orients individual tubular articles collected from a container, in which they are placed randomly.

EP-A-1221502 describes a device in which individual socks or other tubular articles are picked up from a container in which they are placed randomly and are then oriented so that they are always positioned with one of their ends facing forwards by means of a specific pneumatic path and using detection systems capable of distinguishing the elastic band from the toe of the article through different characteristics of elasticity of the fabric.

U.S. Pat. No. 5,769,286 describes a spreading device for longitudinally spreading socks or other tubular knitted articles.

EP-A-178143 describes a further system for detecting the orientation of a tubular textile article by distinguishing between the elastic band and the toe.

U.S. Pat. No. 5,511,501 describes complex machinery, which picks up individual tubular articles from a container in which they are placed randomly and separates them, placing each tubular article in a respective container of a smaller size. Subsequently, each article is picked up from the respective smaller container and fed to a specific pneumatic path inside which the tubular article is oriented so that it is delivered from the pneumatic path always with the same orientation.

U.S. Pat. No. 5,884,822 describes a further device and method for picking up individual tubular articles from a container.

U.S. Pat. No. 5,992,712 describes yet a further device for picking up individual tubular knitted articles and orienting them appropriately.

Similar problems regarding the orientation of tubular articles can be found when feeding stockings or socks to a pressing machine. For example, in the production of women's stockings, the problem exists of inserting each stocking, with the toe already sewn, over a pressing template and for this purpose the individual stockings must be picked up from a container in which they are placed randomly to be inserted over the form. Similar problems also occur in machines for packaging knitwear and hosiery articles, such as stockings and socks.

OBJECTS AND SUMMARY OF THE INVENTION

An object of the present invention is to provide a particularly simple, efficient and reliable device to perform orientation of tubular knitted articles, in particular, although not exclusively, stockings and socks, picked up from a container in which they are placed randomly, to be subsequently fed with the correct orientation towards machines, devices or instruments which perform the subsequent processing on said articles, for example and in particular (although not exclusively) sewing or linking of the toe, pressing or the like.

According to a different aspect, the object of the present invention is to provide a simple and effective method for correct orientation of tubular knitted articles, such as stockings and socks, picked up individually from a container in which they are placed randomly.

In substance, a first aspect of the present invention relates to a device for handling tubular knitted articles having a first end and a second end comprising in combination:

-   -   a first pick-up member and a second pick-up member for said         tubular articles, which can be actuated alternatively to engage         one end of the tubular articles;     -   detection means to determine the orientation of the first and of         the second end of the tubular article, said first and second         pick-up member being controlled to alternatively engage the         tubular article according to the orientation of the tubular         article detected by said detection means.

With an arrangement of this type it is unnecessary to perform detection on the tubular article while it is traveling along the feed path in order to subsequently perform orientation by inverting, if necessary, the direction of feed along the transport duct, as is the case in conventional devices. On the contrary, once the tubular article has been spread and the position of the end to be engaged for subsequent handling operations has been identified, one or other of the two pick-up members is actuated selectively.

In a particularly advantageous embodiment of the invention, the pick-up members are arranged and designed to engage each tubular article at the level of the first end of the tubular article, typically the elastic band, and to open it. It would also be possible for the pick-up members to be designed to engage the other end, i.e. the toe. The choice depends on the handling operations that must be performed on the tubular article in the subsequent processing steps. The edge at which the article is to be engaged is typically elastic when the article is a sock, but it must be understood that this edge could also be non-elastic, for example in the case of women's stockings or components of pantyhose. Moreover, the opposite end can be an open toe, when the function of the device is to feed (with the correct orientation) the articles to sewing or linking means. However, this second end could be a closed toe (sewn or linked), for example when the article is handled to be sent for pressing operations. In general, the device according to the invention is useful each time tubular articles having two structurally different ends are required to be fed in a predetermined direction to members, means, devices or machinery for further processing, said articles being picked up from a container in which they are placed randomly or in any case fed to the device with a random and undefined orientation.

In a practical embodiment, the device according to the invention includes an intermediate station, in which the tubular articles are positioned individually and in sequence in a substantially spread position, with the first and the second end approximately aligned with each other according to the longitudinal extension of the tubular article, said first and said second pick-up member being associated with said intermediate station. The detection means can in this case be advantageously arranged and designed to determine the orientation of the first and of the second end of the tubular article when it is in said intermediate station.

In a practical embodiment of the invention, the detection means are arranged and produced to detect whether said first end of the tubular article located in the intermediate station is positioned in proximity to the first or second pick-up member. Moreover, the pick-up members are controlled so that the tubular article is engaged at its first end by the first or second pick-up member at the level of which said first end is positioned.

Preferably, the detection means are optical means, capable of distinguishing and discerning the two ends of the tubular article from each other on the basis of the shape of the end. For example, the detection means can use a camera interfaced with an electronic processor, or in any case a control unit, equipped with image processing software. In a simpler version, the detection means can include an arrangement of photocells, such as a linear matrix or array, to identify the form of the end of the article which is interposed between the emitters and receivers of the photocells. Detection can be performed with the article at a standstill or with the article moving, on the basis of the sequence with which the photocells are intercepted by the article, said sequence being determined by the form of the article. For example, a linear matrix, i.e. a linear array of photocells can be provided, controlled by specific software capable of identifying with which temporal sequence the photocells are obscured when the article is gradually carried over them. This temporal sequence in fact depends on the shape, or form, of the contour of the article which in turn differs between edge and toe.

Notwithstanding the type of optical detection chosen, it is preferably configured so that the use of particular measures is not required on the articles, such as strips or bands of fabric in a different color to the body of the article, provided purely for the purpose of allowing discernment between the two ends. In fact, these measures cannot always be implemented due to the type of machinery used to produce the articles and, moreover, increase the cost of the article. Further, the device according to the present invention can still be used with detection means which make use of the aforesaid measures to allow recognition of the two ends.

Advantageously, a spreading system can be provided to longitudinally spread said tubular articles and longitudinally align the first and the second end of the articles. Advantageously, in this case the two pick-up members can be associated with the two ends of the spreading system.

According to an advantageous embodiment of the device according to the invention, the spreading device has an inlet for the tubular articles at one of its longitudinal ends and an outlet for the spread articles, which can appropriately be positioned on the side, so that the individual spread articles are delivered in a direction orthogonal to the direction in which they were inserted in the spreading member. The delivery direction of the tubular article from the spreading member is independent from the orientation of the article, which has not yet been identified.

The articles can advantageously be inserted in the spreading system by means of a pneumatic transport duct.

In a possible embodiment of the invention, a conveyor belt is combined with the spreading system to remove the individual tubular articles from said spreading system. This can define the base of an inner volume of said spreading system, the tubular articles being inserted in said inner volume.

According to a possible embodiment, each of the pick-up members has opposed engaging elements designed and controlled to engage and move opposite edges of textile material forming a corresponding end of the tubular article away from each other, to open said end.

According to a possible embodiment of the invention, a respective transfer device is associated with each pick-up member, arranged and designed to transfer a tubular article engaged by the respective pick-up member towards further manipulator members. These further manipulator members are designed and arranged to position each tubular article on a tubular transport member, either directly or after it has passed over a tubular reversing member.

The manipulator members can include a gripper which receives the tubular articles from one or other of said transfer devices. Advantageously, the transfer devices can each include a stretching member designed and arranged to be inserted into the open end of the tubular article, supported by a transfer member which moves the stretching member transferring it towards other manipulator members.

In a possible embodiment, each stretching member is supported by a respective slide actuated with translational motion, forming part of a respective transfer device.

In an improved embodiment of the invention, the pick-up members can be designed so as to directly perform transfer to further manipulator members, such as a gripper to load the tubular article onto a transport tube or the like.

In an advantageous embodiment, a single common stretching device can be associated with the two pick-up members. In this case, each tubular article is carried to the common stretching device, which can comprise mechanical or pneumatic, or combined mechanical and pneumatic engaging means. One or other of the pick-up members is then activated to pick up the tubular article, the end of which has been opened by the stretching device (which is preferably located in an intermediate position between the pick-up members) to transfer the tubular article towards other members, work stations or positions.

The invention also relates to a device for handling tubular knitted articles having a first end and a second end, comprising: an operating position; associated with the operating position, a first pick-up member and a second pick-up member for tubular articles which can be actuated alternatively to engage one or other of the two ends of the tubular articles.

The device can advantageously include detection means to determine the orientation of the first and of the second end of the tubular article, said first pick-up member and said second pick-up member being controlled to engage the tubular article alternatively, according to the orientation of the tubular article detected by said detection means, so that each tubular article is engaged always at the first end notwithstanding its orientation in the operating position. The detection means can be arranged and designed to determine the orientation of the tubular article when it is in the operating position. A control unit can be provided, programmed to receive information from said detection means and to control actuation of one or other of said first pick-up member and of said second pick-up member according to the information received from said detection means.

According to a further aspect, the invention relates to a device for handling tubular knitted articles, such as stockings or socks, with a first end and a second end, provided with two substantially symmetrical pick-up members which can be activated alternatively to engage one or the other of the ends of the article, in combination with detection means to determine the orientation of the article, so that the article is always engaged at one of the two ends by one or the other of the pick-up members, according to the detection implemented by the detection means. According to a possible embodiment, the pick-up members can each include a pair of fingers which can be inserted into the corresponding end of the tubular article. The end which is engaged by one or by the other of the pick-up members can, for example, the elastic edge of the article.

According to a possible embodiment, associated with the two pick-up members is a single common stretching device, that is, a member which opens, stretches or spreads the end of the tubular article to be engaged by the pick-up members. This common stretching device can have a pair of opposed engaging members, mechanical, pneumatic or a combination of mechanical and pneumatic, or of other suitable type, which are arranged and designed to engage and move apart opposite portions of an edge surrounding one or the other of the ends of the article. In a preferred embodiment, the common stretching device is arranged in an intermediate position between the stand-by positions of the pick-up members.

Besides being controlled to alternatively engage the tubular article (depending on how said article is oriented), so that said article is always engaged at the same end, the pick-up members can also be designed and controlled to transfer the tubular article thus engaged towards further manipulator members, such as a transfer device, a loading tube, a gripper for subsequent transfer to a loading tube, a manipulator to insert the tubular article onto an inspection, pressing or finishing template, or for other operations, such as those known in the field of manufacturing stockings, pantyhose, tights and other hosiery articles.

The tubular articles can be conveyed with any known means through various stations of which the device is composed, such as and typically a single or double spreading station, a reading station, a station where the ends are engaged. According to a particular and currently preferred embodiment, said transfer is obtained by arranging the tubular article transversely on a continuous conveyor, i.e. composed of a continuous member which moves along a closed path, such as a mat, a belt, a track, a plurality of slats joined to one another on a flexible belt or chain member, or the like.

According to another aspect, the invention concerns a method for handling tubular articles with a first end and a second end, comprising the steps of:

-   -   picking up a tubular article from a container, in which said         articles are arranged randomly;     -   transferring said article to an operating position, with its         ends approximately aligned according to a direction of         longitudinal extension of the tubular article;     -   recognizing which of the two ends of said article is the first         end;     -   engaging the tubular article at the first end and moving it away         from said operating position.

According to a possible embodiment, the method can include the following steps:

-   -   arranging in said operating position a first pick-up member and         a second pick-up member;     -   controlling said first pick-up member and said second pick-up         member to actuate either said first pick-up member or second         pick-up member in proximity to which said first end of the         tubular article is arranged, to engage said first end of the         tubular article.

In a possible embodiment, the first end of the tubular article, typically the elastic band, is engaged and opened by the respective pick-up member. In another possible embodiment of the invention, the article can also be engaged at the toe and said toe can, for example, be opened.

According to another aspect the invention relates to a method for handling tubular articles with a first end and a second end, comprising the steps of:

-   -   arranging individual tubular articles sequentially in an         operating position;     -   engaging each tubular article at the first end and moving it         away from said operating position.

The method can also include the steps of:

-   -   arranging in said first operating position a first pick-up         member and a second pick-up member;     -   engaging each tubular article alternatively with said first         pick-up member or with said second pick-up member.

In an improved embodiment of the invention, the method also includes the steps of:

-   -   recognizing the position of the first end of an article in the         operating position; and     -   actuating one or other of said first and second pick-up members         always to engage the first end of the tubular article.

According to a possible embodiment of the method according to the invention, the first end of the tubular article can be engaged by a common stretching device, and one or the other of at least two pick-up members can be made to cooperate with said end, according to the orientation taken by the article in the work station.

The invention also relates to a device for handling tubular knitted articles having a first end and a second end, including: a working position; associated with said working position, a first pick-up member and a second pick-up member for the tubular articles, which pick-up members can be activated alternatively to engage one or the other of the two ends of the tubular articles. According to a possible embodiment the pick-up members are designed to open the ends of the tubular article which must be engaged by the pick-up member. In a further possible embodiment of the invention, the first pick-up member and the second pick-up member are combined with a common stretching device, which opens, i.e. stretches the end of the tubular article which must be subsequently engaged by the corresponding pick-up member.

According to an advantageous embodiment of the invention, the first and the second pick-up member in said working position are controlled to engage each tubular article in said working position always at the first end, which can be, for example, the edge or the toe of articles in the form of stockings or socks. The pick-up members are controlled so that they are always activated selectively and alternatively according to the orientation taken by the articles in the operating position. In practice, therefore, the invention consists of a device which by means of at least two pick-up members, engages each tubular article which is carried to a working position or workstation always at a same end, regardless of the random orientation with which said article is placed in the working position or workstation.

The pick-up member can be a member which also opens the tubular article at the end engaged by the pick-up member. In this case, a system to engage the tubular article can be associated with each pick-up member, to subsequently transfer said article to a different workstation. In another embodiment, this pick-up member can be composed of a member to engage the article once it has been stretched at the end thereof, for example by a common device in an intermediate position between the two pick-up members. The pick-up member can be composed of a mechanical member which also transfers the tubular article to a subsequent station.

Further advantageous embodiments of the method and of the device according to the invention are set forth in the appended dependent claims and will be described in greater detail with reference to possible non-limiting examples of embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be better understood following the description and accompanying drawing, which shows a non-limiting practical embodiment of the invention. More specifically, in the drawing:

FIG. 1 shows a perspective view of the container for the tubular knitted articles and of the means which pick up individual articles from the container to send them along a pneumatic path;

FIGS. 2 and 3 show perspective views of means and devices to perform orientation of the tubular articles;

FIG. 4 shows a plan view of the device in FIGS. 2 and 3;

FIG. 5 shows a side view according to V-V in FIG. 4;

FIG. 6 shows a perspective view of the lower part of the devices in FIGS. 2 and 3 with parts removed;

FIG. 7 shows a perspective view of the spreading device of the tubular articles;

FIGS. 8 and 9 show perspective views according to different angles and in different positions of the various members of the transfer devices of the tubular articles and of the gripper which inserts the appropriately oriented tubular articles over the transport tube;

FIG. 10 shows a longitudinal section of the spreading member;

FIG. 11 shows an enlargement of a detail in FIG. 10;

FIGS. 12 to 15 show a operating sequence of the spreading device;

FIGS. 16 to 20 show an operating sequence, with which one of the transfer devices transfers the tubular article to the gripper to allow subsequent transfer to the tubular transport or reversing member;

FIGS. 21 and 22 show axonometric views according to two different angles of a different embodiment of the invention;

FIG. 23 shows a side view according to XXIII-XXIII in FIG. 22;

FIG. 24 shows a longitudinal section of the spreading system to spread the articles in the embodiment according to FIGS. 21-23 and of a corresponding pick-up mechanism of the articles;

FIG. 25 shows a perspective view of the pick-up mechanism in FIG. 24;

FIG. 26 shows a front view of the pick-up mechanism in FIG. 25;

FIGS. 27 and 28 show axonometric views according to two different angles of the spreading system and of the pick-up mechanism in FIG. 24 with the pick-up mechanism separate from the spreading system;

FIG. 29 shows an axonometric view, the same as the one in FIG. 27, but with the spreading system and the pick-up mechanism in a coupled arrangement;

FIG. 30 show an axonometric view of the device in FIGS. 21 to 23, wherein the mechanical parts of all the stations have been removed with the exception of the parts of the station for reading or detecting the orientation of the article, limited to the members for moving the articles;

FIGS. 31 and 32 show said members for moving the articles in two different operating positions;

FIG. 33 shows a perspective view of the stretching members which open the end of the tubular article;

FIGS. 34 to 39 show axonometric views in various operating positions of the pick-up members, of the respective actuators and of the mechanical elements associated therewith;

FIG. 40 shows a front view of the pick-up members, according to the line XL-XL in FIG. 41;

FIG. 41 shows a plan view according to XLI-XLI in FIG. 40;

FIG. 42 shows a side view according to XLII-XLII in FIG. 41;

FIGS. 43A to 43Q show schematic views representing an operating cycle of the device shown in FIGS. 21-42.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION Embodiment in FIGS. 1 to 20

A device incorporating the present invention and which has the function of loading socks provided with an elastic band and an open toe onto a transport tube to convey the individual socks to a sewing machine is described below. However, it must be understood that the principles and the specific technical solutions described herein can also be utilized in other machinery, which handle, for example, tubular articles with a non-elastic open band and/or with the toe already sewn, for example to load the articles onto pressing templates, in a packaging machine, or the like.

FIG. 1 shows a perspective view of the container in which the tubular articles are placed randomly to be subsequently picked up, the pick-up means and the beginning of the pneumatic transport path with which the individual tubular articles are sent to the devices provided for their orientation.

In FIG. 1 the number 3 indicates a container which receives randomly arranged tubular articles which can, for example, come from a series of circular knitting machines. The container 3 can rotate according to the arrow f3 about a vertical axis by means of a motor, not shown. The number 5 generically indicates a pick-up device, of known type, which moves vertically according to the double arrow f5 along a vertical guide, at the level of which the inlet 7A of a pneumatic transport duct 7 is positioned. The individual tubular articles picked up by the pick-up device 5 are sucked with random orientation through the inlet 7A into the suction duct 7. The latter extends to a spreading member which is positioned in a subsequent station of the device, illustrated in detail with reference to the subsequent figures.

Connected to the pneumatic transport duct 7 is a pneumatic return duct 11, which transfers, through an unloading device 13, any tubular articles which cannot be further handled, for example, when the pick-up device 5 due to an operating error picks up two tubular knitted articles simultaneously and feeds them to the pneumatic transport duct 7.

The numbers 105 and 111 indicate gate valves or valves used to open and close the individual branches of the pneumatic paths, and in particular the pneumatic duct 7 and the pneumatic return duct 11. The number 103 indicates a connection with a suction line, not shown, for example connected to a suction fan.

With reference to FIGS. 2 to 11, the members used to correctly orient each tubular knitted article fed into the pneumatic transport duct 7 will now be described.

In FIGS. 2 and 3, the number 21 indicates as a whole the assembly of the machines, devices and equipment required to orient the tubular articles and transfer them to a tubular transport member 23 or to a tubular reversing member 25. The tubular transport member 23 can be part of a more complex machine, optionally with several stations, used to transfer the tubular knitted article to a sewing or linking machine. The machine incorporating the transport member 23 and the sewing machine do not form the object of the present invention and, therefore, are not represented.

The tubular reversing member 25 is employed, as will be more apparent below, when the individual tubular articles fed to the assembly of equipment 21 must be reversed to turn the finished tubular article inside out.

With specific reference to FIGS. 2 to 5, the number 7B indicates the end of the pneumatic transport duct 7, opposite the inlet 7A (FIG. 1). The end section 7B is represented with a rectangular shape, but this is not strictly essential.

The end 7B of the transport duct 7 terminates at a first end of a spreading device indicated as a whole with 27, inside which each tubular article fed through the pneumatic duct 7 is spread to position the first end (e.g. the elastic band) and the second end (e.g. the toe to be closed) of the tubular article aligned according to the longitudinal extension of the tubular article.

The internal structure of the spreading device 27 and its operating modes will be described in greater detail with reference to FIGS. 10 to 15. For the moment it is sufficient to point out that the individual tubular articles inserted onto the spreading device 27 each time with a random orientation (i.e. with the first end or the second end being the leading end with respect to the direction of insertion) are delivered from the side of the spreading device 27 again in a random orientation, but with the aforesaid two ends aligned according to the longitudinal extension of the tubular article. The base of the spreading device 27 is defined by a conveyor belt 29, which moves according to the arrow f29 controlled by a motor 30 (FIG. 3).

A load-bearing structure 31, which also supports the spreading device 27 and the conveyor belt 29, supports a second conveyor belt 33 provided with a movement according to the double arrow f33 in a direction oriented substantially through 90° with respect to the direction f29 of the movement of the conveyor belt 29. The motor 35 (FIGS. 2 to 4) provides the movement for the conveyor belt 33.

The conveyor belt 33 is supported by side elements 37, to which the motor 35 is also fastened, which can move towards and away from each other with respect to the conveyor belt 29 below moving in the direction of the double arrow f37 for the purposes described below. The lifting and lowering movement of the side elements 37 is provided by an actuator 39 (FIG. 3) of pneumatic, hydraulic or similar type.

When an individual tubular article is delivered from the side of the spreading device 27 conveyed out of it by the conveyor belt 29, it must be transferred with a movement parallel to its longitudinal extension under a detection means to detect which of the two ends is the toe, or the elastic edge. In substance, the individual tubular article must be arranged at the level of at least one system capable of recognizing and distinguishing the two ends of the tubular article from each other. In the embodiment illustrated schematically here, the detection means include a camera 41 (represented schematically only in FIG. 4) or another suitable viewing system which, for reasons of economy, is provided only on one side of the conveyor belt 29, but could also be provided on the opposite side. Instead of a viewing system, such as a camera 41 or the like, the detection means could be of another kind. For example, systems could be provided which are capable of distinguishing the color of an elastic band or strip surrounding the open toe of the tubular article, and which has a different color from the rest of the fabric of the tubular article. In this case the detection means could, for example, include photocells or the like. However, this solution, has the drawback of increasing the production cost of the articles.

Yet again, alternatively or in combination, a system capable of recognizing the presence of conductive materials, such as a metal thread, inserted in the band surrounding the toe of the tubular article to be closed, could be provided as detection means.

Yet again, alternatively or in combination, detection means could be provided which are based on recognition and discernment of the two ends of the tubular article through characteristics of elasticity, thickness, or of another nature, of said article.

Alternatively or in combination, in a preferred solution it would also be possible to use a system of photocells arranged according to a geometrical configuration which allows recognition of the form of the end of the article which is interposed between emitters and receiver of the photocell, to distinguish the elastic edge from the toe. Various types of devices having this functionality are known and those skilled in the art can easily select the most suitable detection or recognition device for the particular application.

In any case, the detection means can be single or double, i.e. present on only one side or on both sides of the conveyor belt 29, although to economize it would be preferably for them to be provided only on one side.

As the tubular knitted article, which is delivered from the side of spreading device 27, is positioned on the conveyor belt 29, it must be translated longitudinally to be taken with one of its ends, which has yet to be determined whether it is the toe or the elastic edge, to the level of the detection means 41. The transverse conveyor belt 33 positioned over the conveyor belt 29 has the function of translating the tubular article parallel to its longitudinal extension, according to the arrow f33, to take the end closest to the detection means 41 and under said means. To allow this translational movement of the tubular knitted article the surface of the conveyor belt 29 has a coefficient of friction at least slightly lower than the coefficient of friction of the conveyor belt 33, so that when the conveyor belt 33 is taken with its lower branch to press against the tubular article which is located on the conveyor belt 29, the movement imparted by the motor 35 to the conveyor belt 33 causes the tubular article to slide on the upper surface of the conveyor belt 29 until it is under the detection means 41.

It would also be possible to move the detection means 41 while the article remains at a standstill.

As mentioned, the purpose of these detection means 41 is to recognize whether the end of the tubular article positioned under them is the first end (e.g. the elastic band) or the second end (e.g. the toe), in order to communicate the effective orientation of the tubular article on the conveyor belt 29 to a central control unit (indicated schematically with 42 in FIG. 4).

As the tubular article must be removed from the operating station or position, or intermediate station, in which the spreading device 27 and the conveyor belt 29 are located always with one of its ends being the leading end, i.e. always with the same orientation, for each tubular knitted article to be inserted over the tubular reversing member 25, or over the tubular transport member 23 always with the correct end, and typically with the elastic band, two groups of essentially symmetrical members 51A and 51B are arranged at the two sides of the conveyor belt 29, which are used to open and stretch the end of the tubular article to be subsequently inserted over one or over the other of the tubular members 23, 25. These groups 51A, 51B include pick-up and transfer members for the tubular articles. The one of said group or pick-up members 51A, 51B is actuated, at the level of which the end of the tubular article is positioned, which is to be opened and inserted over one or other of the members 23, 25. The members and the mechanisms forming the two symmetrical groups 51A, 51B are indicated with the same reference numbers followed by the letters A or B.

Each of the groups 51A, 51B firstly has a fixed suction surface 53A, 53B provided on a flat sliding surface 55A, 55B positioned along the side of the conveyor belt 29. Arranged over the suction surface 53B is a respective pick-up means 57A, 57B provided with a vertical movement imparted by an actuator 59A, 59B. The pick-up means 57A, 57B can thus move towards the corresponding suction surface 53A, 53B and away therefrom. The suction surface 53A, 53B and the corresponding pick-up means 57A, 57B with its actuator 59A, 59B form means to alternatively engage the elastic band, i.e. the first end of the tubular article which is brought over the suction surface 53A or 53B to open said end.

Each group 51A, 51B also includes a stretching device, composed in this embodiment of a pair of fingers 61A or 61B, In the FIGS. 2, 3, 4 and 5, the fingers 61A, 61B are represented in the two different positions, vertical and horizontal respectively, which the fingers take during the operating cycle as will be explained in greater detail below. These fingers are in turn supported by respective transfer devices, which transfer the articles engaged by the stretching devices composed of the fingers 61A, 61B towards further handling means, as will be described below.

FIG. 8 shows the fingers 61A and 61B in various possible positions. More specifically, the fingers 61A are represented in FIG. 8 in their vertical position, while the fingers 61B are represented in the horizontal and vertical arrangements, in two distinct positions the pair of fingers can take along the front of the conveyor belt 29 to pick up the individual article and transfer it towards a gripper, described below, which inserts the article over one or other of the tubular members 23 and 25.

The two fingers 61A, 61B of each pair can be moved towards and away from each other by means of a piston-cylinder actuator 63A, 63B. The pair of fingers, with the respective actuator 61A, 63A or 61B, 63B, are supported on a support 65A or 65B movable vertically according to the double arrow f65 controlled by an actuator 67A or 67B (see in particular FIGS. 5 and 6).

The piston-cylinder actuator 67A or 67B is supported by a slider 69A, 69B. Integral with the slider is a rack 71A or 71B, meshing with which is a pinion 73A, or 73B, keyed on a shaft 75A or 75B, attached to the opposite end of which are the fingers 61A, 61B with the respective actuator 63A, 63B which moves them towards and away from each other. With this arrangement, a vertical lifting and lower movement of the support 65B or 65A controlled by the actuator 67B or 67A, besides a lifting and lowering movement of the respective fingers 61B, 61A, also causes rotation of the fingers about the axis of the corresponding shaft 75B, 75A.

The two sliders 69A and 69B are supported (see in particular FIG. 6) by respective slides 77A, 77B. The two slides 77A, 77B move slidingly along a common guide 79 and their movement is controlled by two parallel threaded bars 81A and 81B made to rotate by respective motors 83A, 83B. The threaded bars 81A, 81B engage in female screws 85A, 85B integral with the slides 77A, 77B. The motors 83A, 83B therefore cause movement of one or other of the stretching devices composed of the pairs of fingers 61A, 61B according to the double arrow f61 (FIG. 6). The slides and sliders form the transfer devices or means which support the pairs of fingers towards the central zone of the device where they transfer the tubular articles to a gripper described below, which then inserts them over one or other of the tubular members 23, 25.

Each slide 77A, 77B in turn supports a guide 87A, 87B on which the respective slider 69A, 69B slides. This slider is provided with a movement according to the double arrow f69 in a direction orthogonal to the direction of the guide 79. This movement according to the arrow f69 is imparted to one or other of the two sliders 69A, 69B by a cam and tappet mechanism. This mechanism has a track which forms a cam profile 91, inside which two idle pins 93A, 93B, integral with respective sliders 69A, 69B, engage. The profile of the channel 91 is substantially symmetrical with respect to a vertical median plane and is configured so that a translational movement of one or other of the sliders 69A, 69B with their respective slides 77A, 77B in the direction of the arrow f61 from the position farthest from the median plane to the position closest to the median plane of the device causes the slider 69A, or 69B to move away with respect to the position of the spreading device 27.

With reference to the example in FIG. 6, the pair of fingers 61A with the respective members supporting them are represented in two distinct positions, respectively the external side position (on the right in FIG. 6), and the intermediate or internal position (central in FIG. 6). On the other hand, the fingers 61B with the respective members which support and move them are in their external side position.

The functions of the various movements described herein will be explained below with reference to an operating sequence of the entire device.

FIGS. 7, 10 and 11 show in greater detail the configuration of the spreading device 27. It includes a box structure 150 with a rectangular section, connected to which are the end 7B of the pneumatic transport duct 7 and a suction mouth 151. The box structure 150 has a side panel 153 attached to a piston-cylinder actuator 155 supported by the upper horizontal wall of the box structure 150. The actuator 155 can control a lifting and lowering movement of the side panel 153 to open and close the box structure 150. The conveyor belt 29, runs along the bottom of the box structure 150, in substance defining the lower surface of the compartment or inner volume with rectangular section of the spreading device 27. The lifting movement of the side panel 153 allows the tubular article inside the spreading device 27 to be delivered from the side and transferred out of the spreading device by the conveyor belt 29.

In the central zone of the box structure 150 the spreading device has movable pressers 161 actuated by actuators 163 (five in number in the example shown) which have the dual function, described in greater detail below with reference to an operating sequence, of reducing the cross section of the compartment or inner volume of the spreading device 27, reducing the vertical dimension, during the spreading step of the tubular article, and of allowing complete and correct spreading of said article also at its end which is inserted into the spreading device 27 first.

As can be seen in particular in FIGS. 10 and 11, a screen 165 is arranged between the inside of the spreading device 27 and the suction mouth 151 to prevent the tubular articles penetrating the spreading device 27 from being sucked inside the suction mouth 151. In the example shown the screen 165 is arranged inclined to define a substantially cuneiform volume, arranged at the narrow end of which is a retention member 167, controlled by a piston-cylinder actuator 169 (FIG. 11), provided to retain the end of the tubular article orientated forward with respect to the direction of insertion of the tubular article in the spreading device 27. Due to the configuration of the device, the retention member 167 engages one article at a time. If two tubular articles are accidentally fed into the box structure 150 one of them is engaged by the retention member and the other is carried back by suction and returned to the container 3. Consequently, the device 27 also functions as a separator and not just as a spreading device.

Alternatively, the screen 165 can be arranged on a surface approximately orthogonal to the direction from which the tubular articles are fed and the retention member can, for example, be composed of a gripper.

The box structure 150 is supported slidingly in the direction of the double arrow f150 to perform a transverse movement with respect to the direction of movement f29 of the conveyor belt 29. This transverse movement according to f150 of the box structure 150 of the spreading device 27 is imparted by a piston-cylinder actuator 171 and its purpose will be described with reference to an operating sequence of the machine.

Arranged in an intermediate position along the front of the conveyor belt 29 are the tubular members 23 and 25, the latter supported by a fixed structure 26, while the tubular member 23 is attached, for example, to a conveyor, not shown, of a machine which loads the tubular articles onto the sewing or linking machine.

At the level of the tubular members 23, 25 (which are superimposed and substantially coaxial with each other), is a gripper, indicated as a whole with 180, the function of which is to receive the individual tubular articles picked up from the pair of fingers 61A or 61B, stretch the elastic band and insert it alternatively over the upper tubular member 25 or over the lower tubular member 23.

The gripper 180 has a rotational movement through 180° around a vertical axis, imparted by means of a piston-cylinder actuator 183 supported by a slide 185 which also supports the gripper assembly 180. The piston-cylinder actuator 183 controls a rack 187 (see in particular FIG. 16), meshing with which is a pinion (not visible) integral with a shaft which supports the gripper 180. The linear movement of the piston-cylinder actuator 183 thereby causes rotation of the entire gripper assembly 180 through 1800 about the axis A-A (FIG. 9). The purpose of this rotation is to allow the gripper to transfer the tubular article engaged by it (in the manner to be described below) alternatively to the tubular member 25 or to the tubular member 23.

The slide 185 is provided with a vertical movement according to the double arrow f185 along a vertical guide 188. The vertical movement is obtained by means of a transmission belt 189 and a motor 190 arranged at the upper end of the guide 188. The movement according to the double arrow f185 allows the gripper to transfer the tubular article to the corresponding end of the tubular member 25 or 23.

The gripper 180 is composed of two flat jaws 201 supported by brackets 203. The two jaws 201 each cooperate externally with a pair of bars 205 which, as shall be apparent below, are used to block the elastic band of the tubular article on the jaws 201. The movement of the jaws 201 towards and away from each other is controlled by two piston-cylinder actuators 207, 209.

Operation of the entire machine described above is illustrated with specific reference to FIGS. 12 to 20, in which FIGS. 12 to 15 show in particular the operating functions of the spreading device 27, while FIGS. 16 to 20 show the methods with which a tubular article, spread in the spreading device 27 and the orientation of which has been recognized, is loaded on one or other of the tubular members 23, 25. The various members and actuators of the device are controlled, to perform the operations described below, by a microprocessor or by a programmable unit indicated schematically with 2 only in FIG. 4 and connected to the various actuators, encoders and other means, not described and known, employed on the device to control the various movements.

An individual tubular article M is picked up by the pick-up device 5 from the rotating container 1 and sucked inside the pneumatic transport tube 7, which leads into the inner compartment of the spreading device 27. The suction that transports the tubular article from the inlet 7A of the pneumatic duct 7 inside the spreading device 27 is applied through the suction mouth 151.

In FIG. 12 the tubular article M is entering, sucked through the mouth 151, the compartment of the spreading device 27 and reaching with one of its ends (which can either be the elastic band or the toe without distinction and randomly) the inclined end screen 165. Travel of the tubular article M terminates according to the arrow F against said screen and the tubular article is clamped (FIG. 13) by the retention member 167 actuated by the actuator 169. At this point the individual pressers 161 associated with the spreading device 27 can be lowered to halfway through their travel by the actuators 163 to take the position shown in FIG. 13. In substance, this reduces, at least in the central zone, the cross section (more specifically the height) of the inner compartment of the spreading system or device 27.

By inverting suction inside the duct which connects in 7B with the inner compartment of the spreading device 27, the tubular article M is pulled and spread with a force applied by the air flow in the direction of the arrow F1 in FIG. 13, while the end of the tubular article M engaged against the screen 165 remains fastened there.

At this point, the tubular article M is in the spread position inside the volume of the spreading device 27. If two tubular articles are fed inside the spreading device 27 by error, the second tubular article will not be engaged by the retention member 167, thanks to the particularly narrow configuration of the end zone of the cuneiform volume defined by the screen 165 and will therefore be unloaded through the device 13 and the unloading duct 11 into the container 1 through inversion of suction. In fact, in this step suction inside the spreading device 27, a portion of the duct 7 and the pneumatic duct 11 is produced through the suction mouth 103, the gate valve 111 being open and the gate valve 105 being closed.

After the tubular article M has reached the spread position inside the volume 150 of the spreading device 27, the box structure of the spreading device is translated to the left (in the figure) by means of the piston-cylinder actuator 171 to take the position in FIG. 14. In this way the tubular article M is practically positioned entirely over the conveyor belt 29 which defines the base of the inner compartment of the spreading device 27. In the subsequent operating step (FIG. 15) the presser 161 which is closest to the end of the article M that entered the inner compartment of the spreading device 27 last is lowered to press the article M against the conveyor belt 29 below. As the tubular articles M which are in the container 1 are all substantially of the same dimension, i.e. of the same size, it is known a priori which of the five pressers 161 is positioned closest to this end of the tubular article M. This allows the correct presser to be actuated by the control unit 28. Alternatively, optical sensors could be provided inside the spreading device 27 to identify the position of the end of the tubular article M that entered the inner compartment of the spreading device 27 last. The other pressers 161, positioned to the left of the lowered presser 161 (i.e. on the opposite side with respect to the end in which the screen 165 is positioned), can also be moved downwards, to prevent any portion of the article M projecting slightly from the presser in question from being folded over itself when suction through the screen 151 is actuated again.

With the tubular article M engaged in this way against the upper surface of the conveyor belt 29, the box structure 150 of the spreading device 27 can be translated again from left to right (in the figure) by the actuator 171 to be returned to the position in FIG. 15. In this step suction can also be actuated again through the suction mouth 151 to correctly spread the end of the tubular article M which was previously engaged by the retention member 167 and which may not be perfectly aligned with respect to the longitudinal extension of the article M.

At the end of these operations the side panel 153 of the box structure 150 of the spreading device 27 is lifted by the actuator 155 and the conveyor belt 29 is actuated to transfer the spread tubular article out of the inner compartment of the spreading device 27.

In a subsequent step, not shown, the tubular article M is translated in a transverse direction with respect to the direction of feed of the conveyor belt 29, by means of the conveyor belt 33 until its end which entered the spreading device 27 last is under the camera 41 or other detection means arranged on one of the two sides of the conveyor belt 29. The camera is capable of distinguishing whether the end of the article under it (i.e. the end which entered the spreading device 27 last) is the toe or the elastic band of said article, i.e. if it is the second or the first end of the article.

As the article M must be engaged by pick-up means 53B, 57B or 53A, 57A at the level of its elastic band, according to the detection performed by the camera detection means 41 or other equivalent devices, the unit 28 controls the subsequent movement of the conveyor belts 33 and 29, which is coordinated to take the tubular article M with its elastic edge at the level of the pick-up means and in particular with its elastic band resting on the suction surface 53A or 53B.

Evidently, the tubular article M is in this way transferred from one or other of the symmetrical groups 51A, 51B according to the position of the elastic band, which is random as the tubular article is picked up from the container 1 in a random position.

FIG. 16 shows the subsequent step in which the tubular article M has already been positioned with the coordinated movement of the conveyor belts 29, 33, with its elastic band B at the level of the group 51A. Evidently, in this example the tubular article M entered the spreading device 27 with its elastic band facing forward and with the toe P representing the second end of the tubular article downstream of the elastic band B with respect to the direction of feed of the tubular article M inside the pneumatic transport duct 7.

If the tubular article M had entered the suction duct 7 with the opposite orientation, i.e. with the elastic edge B at the back and the toe P at the front, it would have been transferred with the elastic band B at the level of the group 51B. In the example illustrated the subsequent steps will be performed on the elastic band B by the group 51A. If the tubular article M had been facing in the opposite direction the group 51B would have been used instead, to perform the subsequent operations.

From the layout in FIG. 16, the tubular article M is engaged by the pick-up means 53A, 57A, which move reciprocally towards each other with the elastic band B of the article interposed therebetween. By actuating suction through the suction surfaces 53A and actuating the pick-up means 57A and subsequently reciprocally moving these two elements away from each other by means of the actuator 59A, the opposed edges forming the elastic band B of the article are slightly distanced. The fingers 61A, which in FIG. 16 are shown parted, are moved towards each other and inserted inside the open elastic band B. Subsequently, the fingers are parted to stretch the band B elastically.

Once the band B has been engaged by the stretching fingers 61A, by means of the handling members described with specific reference to FIG. 6, these fingers are translated from the side position to the intermediate position (the two positions are indicated in FIG. 6). The fingers 61A are also rotated clockwise through 90° to be taken to the vertical position.

When the fingers 61A are in the intermediate position they are placed above the gripper 180, as shown in the layout in FIG. 17. The tubular article M is still engaged with its elastic band B by the parted fingers 61A. The jaws 201 of the gripper 180 are moved towards each other, so that a relative vertical movement between the fingers 61A and the gripper 180 carries these members to the relative position in FIG. 18, with the fingers 61A under the central brackets 203 which support the plates forming the jaws 201 of the gripper 180. As the jaws 201 are moved towards each other and the fingers 61A move with respect thereto until they are lowered under the brackets 203, the tubular article M is transferred with this relative movement from the fingers 61A to the jaws 201, the elastic band B being arranged around the jaws 201 of the gripper 180 as shown in FIG. 18.

After reaching this position, also visible in the perspective view in FIG. 19, the jaws 201 of the gripper 180 can open to stretch the elastic band B of the article M until it has a quadrangular cross section as shown in FIG. 20. The end of the tubular article M composed of the elastic band B is in this way enlarged to a sufficient extent to allow the gripper 180 to transfer the tubular article onto one or other of the two tubular members 23 or 25.

The overturning movement through 180 degrees which the gripper 180 can perform by means of the actuator 183 allows the mouth of the tubular article to be positioned facing the lower tubular member 23 (position in FIG. 20) or facing the upper tubular member 25.

When the tubular article M is fed from a double cylinder circular knitting machine it is already reversed, i.e. with its inner surface facing outwards. In this case the tubular article M is inserted directly onto the lower tubular transport member 23. If, on the other hand, the tubular article M is fed from a single cylinder circular machine, it must be reversed to take the surface normally on the inside to the outside before it is sewn. For this purpose, the gripper 180 rotates through 180° about the horizontal axis to insert the elastic edge B of the article over the upper tubular reversing member 25, which in a known way reverses the tubular article by means of additional members, not shown. The reversed tubular article is then transferred to the lower tubular transport member 23.

As will be clear from the description above of the structure and of the functions of the various members of the machine, it is capable of performing the following functions in parallel:

-   -   spreading and separating in the device 27;     -   detecting the end of the article on the conveyor belt 29;     -   opening the edge of the end.

Therefore, three distinct tubular articles, on which the aforesaid operations are performed in succession, can be present at all times in the machine.

Embodiment in FIGS. 21 to 43

FIGS. 21-43 show another embodiment of the device according to the invention. The same numbers indicate the same or corresponding parts in the various figures. In this embodiment, the device can be combined with a container for tubular articles, associated with which is a means to pick up the individual articles with a configuration substantially the same as the one shown in FIG. 1 described above. The container for collection of the articles to be handled and the pick-up members of the articles can also differ from those shown in FIG. 1 and be designed according to other criteria known in the state of the art or within the ability of those skilled in the art. The only relevant fact is that the articles, preferably already separated one from the other, are fed to the device that performs orientation thereof.

The members which spread the tubular articles longitudinally, detect their orientation and pick-up the end of the article to be handled are shown in FIGS. 21 to 42. They will be described in detail hereunder and operation thereof will subsequently be explained on the basis of FIGS. 43A-43Q. They can be positioned at least partly overlapping the container shown in FIG. 1, in order to reduce the overall dimensions.

The suction duct 7 (FIG. 1) feeds the individual tubular articles to a device represented as a whole in FIGS. 21 to 23, and indicated generically with 501. This device comprises a conveyor 503 which moves the individual articles forward in steps according to arrow F. The slatted conveyor 503 is composed of individual slats 503A, constrained to a flexible member, such as one or more chains, not shown. Strips 503B are fastened to some of the slats 503A to define individual seats for the articles to be moved forward along the path of the device.

As in the embodiment shown in FIGS. 1 to 20, in the device 501 the individual articles fed to the device are also first spread longitudinally, it being understood that each article is spread with the longitudinal extension thereof oriented transversely with respect to the direction of feed F of the conveyor member 503. To spread each article, the device 501 has a double station and a double spreading system or device described hereunder. In FIG. 23, the numerals 507 and 509 indicate as a whole the two stations or positions in which the two spreading members that perform longitudinal spreading of each article are located. More specifically, a first spreading system 510, to which the suction duct 7 connects in 7B and the structure of which is described in detail hereunder with reference to FIGS. 24 to 29, is located in the station 507.

The connector 7B leads into a compartment with a rectangular cross section 513 which has, at the opposite end with respect to the connector 7B, a shutter 515 having the function of modifying the conformation of the section of passage defined by the compartment 513, constricting it in a specific operating phase. The shutter 515 has a shutter element 515A controlled to translate according to the double arrow f515 orthogonal to the longitudinal axis of the compartment 513, by means of a piston-cylinder actuator or other suitable actuator shown at 517. As can be seen in particular in FIG. 27, the shutter 515 has a shape with a semi-circular lower edge, or more generally with a curved and convex cross section, approximately the same as the shape of the semi-circular cross section of the end portion 513A of the suction compartment 513. When the shutter element 515A of the shutter 515 is in the position shown in FIGS. 24 and 27, it defines with the inner wall of the portion 513A of the compartment 513 a passage with a narrow and shaped cross section, extending approximately in a semi-circumference, which (as will be explained hereunder) tends to flatten the tubular article.

Integral with the spreading system 510 is a suction mouth 521, connected to which is a suction duct 523, of which only the initial portion is shown in the drawing.

Cooperating with the spreading system 510 is a mechanism 525 to pick up the tubular articles which are sucked inside the spreading system 510 and which has the function of pulling each tubular article through the section of passage defined by the inner wall of the end portion 513A of the compartment 513 and by the shutter element 515A described above.

The mechanism 525 is supported by a slide 527, movable according to the double arrow f525 along a guide 529. Movement of the slide 527 is controlled by a belt 531 operated by a motor 533 and entrained around two pulleys. The mechanism 525 is constrained to the slide 527 by means of a piston-cylinder actuator 535 which controls the lifting and lowering movement in a vertical direction according to the double arrow f525X of the mechanism 525. The lifting and lowering movement of the mechanism 525 has the function of positioning said mechanism in line with the spreading system 510 and, alternatively, above the latter. This facilitates and improves the efficiency of flattening of the article when it is made to pass through the shutter 515, as the article is pulled against the shutter element 515A.

The mechanism 525 comprises an approximately box-shaped compartment 539, inside which a vacuum can be created by means of suction through an aperture 541 which is connected with a tubular connector 543 through a suction box 543A. The tubular connector 543 can be connected to the suction mouth 521 of the spreading system 510. This pneumatic connection is achieved by moving mechanism 525 along with its connector 543 according to the arrow f525 towards the suction mouth 521 and therefore towards the spreading system 5101, to make the elements 510, 525 take the reciprocal position shown in FIG. 29. In this arrangement suction implemented through the suction duct 523 causes suction through the box-shaped compartment 539, the suction compartment 513 and the duct 7, 7B. Inside the box-shaped compartment 539 is a grid 545 composed (FIG. 26) of a series of teeth 545A with a front edge (i.e. oriented towards the spreading system 510) inclined with respect to the horizontal. Associated with this grid formed by the teeth 545A is a retaining pawl 547 the movement of which according to the double arrow f547 is controlled by a piston cylinder actuator 549 supported by the mechanism 525. Combined with the grid 545 formed of the teeth 545A and of the pawl 547 is a presser 551, provided with a vertical movement according to the double arrow f551 controlled by a piston cylinder actuator 553. The presser 551 has a C-shape open towards the grid 545. The purpose thereof is to retain the tubular article during the spreading or flattening phase, acting thereon with a sufficiently wide surface to prevent the article from being damaged.

Operation of the spreading system and of the relative mechanism 525 described above will be explained later on with reference to the detailed description of an operating cycle of the device.

In the station 509 is another spreading system 510X which has members equivalent to those described with reference to the spreading system 510, indicated in the figures with the same reference numbers followed by the letter X. The suction compartment 513X with rectangular section is connected to a suction duct indicated with 8B and corresponding to the suction duct 7B. As opposed to a mechanism like the one indicated with 525, the spreading system 510X located in station 509 cooperates with a simple conveyor belt or mat 563 supported by a supporting structure 565 of the device and provided with a movement according to f563 imparted by a motor 565. The conveyor belt 563 is driven about rollers which are supported, together with the motor 565 and the other members transmitting motion to the conveyor belt 563, by side panels 567 which move vertically by means of piston cylinder actuators 569, to allow the conveyor belt 563 to move towards or away from the conveyor 503. The conveyor belt 563 moves each individual article longitudinally, i.e. parallel to the extension thereof, in a transverse direction with respect to the direction of feed F of the conveyor belt 503 to take each tubular article inside the spreading system 510X and remove it gradually therefrom when the shutter element, equivalent to the shutter element 515A, is in the substantially closed position and suction continues through the slot it leaves open.

Downstream of the second spreading station 509 (with respect to the direction of feed F of the articles by conveyor 503) is a station 570 for detecting the ends of the tubular article. Located in this station is a presser 571, provided with a vertical lifting and lowering movement according to the double arrow f571 to press against the slats 503A forming the continuous conveyor 503, or to be lifted therefrom. The lifting and lowering movement of the presser 571 is controlled by an actuator 573 (FIG. 30) supported by a slide 575 constrained to a belt 577. The belt 577 takes its motion from an actuator 579 and imparts an alternate rectilinear horizontal movement, according to the double arrow f575, to the slide 575, to the actuator 573 and finally to the presser 571. The presser 571 is therefore provided with a double movement: vertical according to f571 and horizontal according to f575 in a transverse direction with respect to the direction of feed F of the conveyor 503.

The presser 571 is positioned between two inclined profiles 581A, 581B which extend transversely to the direction of feed F of the articles, i.e. parallel to the slats 503 of the conveyor 503. The profiles 581A, 581B are supported by a cross-member 583, in turn supported by piston-cylinder actuators 585 interposed with the fixed structure 565. At the ends thereof, the cross member 583 supports actuator and guide systems 587, to which the profiles 581A, 581B are constrained, and which have the function of imparting a movement according to the double arrow f581 to the profiles 581A, 581B. In substance, the profiles 581A, 581B can be moved towards and away from each other. They have the function of centering each individual article which is positioned between the two profiles 581A, 581B.

At the station 570, located on the side of the conveyor 503 is a detection device which can comprise a camera, the images of which are processed by a suitable image recognition software, or a series of photocells or other means in general suitable to recognize, i.e. to distinguish the two ends of each tubular article inserted in the device from each other. This detection system is indicated generically with 590 in the figure, and can be supported by a C-shaped profile, which holds, for example, a series of photoemitters and an opposed series of photoreceivers, between which the end of each article closest to the sensor or detection device 590 is inserted.

To carry the article with the end thereof under the detection elements the previously described presser 571 is provided, and for this purpose it is lowered to press the article gently against the conveyor 503 and then, by translating horizontally (arrow f575), to take it to the desired position. This is made possible by the low coefficient of friction with which the slats 503A forming the conveyor 503 are produced.

In place of photocells, cameras or other optical reading systems, the detection device 590 can also use other mechanisms. For example, the two ends of each article could be made recognizable and distinguishable by inserting a specific material in only one and not the other of the two ends. For example, a metal yarn, a magnetic thread or the like could be inserted in one of the two ends (preferably the toe to be sewn when the articles being handled are stockings or socks). Recognition of these threads can take place with a capacitive sensor, a magnetic sensor or other suitable mechanism.

In general, the present invention is not limited to the type of reading or distinguishing mechanism to recognize and distinguish the two ends of each article from each other. However, and preferably, optical systems capable of recognizing and distinguishing the two ends on the basis of their geometrical conformation are used, as with these systems it is possible to avoid using special materials during production of the articles and therefore the device according to the invention can be more generally used and the manufacturing costs of the articles are reduced, by avoiding the need to carry out special procedures in the production steps upstream.

As can be seen in particular in FIG. 33, in a specific area the slats 503A of the conveyor 503 have a series of holes 503C. In the drawing, these holes are indicated only for some of the slats 503A, to simplify representation, but it must be understood that in actual fact a band of perforations, slots or the like is found along the entire continuous extension of the conveyor 503. In other words, each of the slats 503A is provided with an open area through which the subsequent reading operation can be performed to transversely position the article to allow subsequent handling in the station 600 to be described in detail hereunder. More specifically, each slat has suction holes and, at the two ends of the area perforated for suction, two holes for corresponding photocells or other optical readers for positioning the tubular article, which are located under the perforated area 503C of the slats 503A. In place of optical readers, other suitable sensor means can be used.

With this arrangement, once the article has been taken under the sensors or other detection members 590 and after the electronic control system of the device 501 has checked whether the end positioned under the detection systems 590 is the first or second end, with a horizontal movement of the presser 571 in one direction or the other, the article can be translated transversely with respect to the direction F of feed, to take the desired end to the apertures or slots 503C. This is the position the article must be in, to be able to proceed, in the subsequent station 600, with opening of the end of the article and consequently engage it by means of the engaging members of the station 600.

In practice, movement of the presser 571 is controlled so that the end of the article to be subsequently engaged by the pick-up members is always positioned on the apertures 503C. If the article to be handled is a sock, which must always be engaged at the elastic edge, movement of the presser 571 will be controlled to take said elastic edge to the perforated area 503C. If the elastic edge is the end recognized by the detection system 590, the presser 571 will move away from the detection system 590. Vice versa, if the end identified by the detection system 590 is the toe, this means that the opposite end must be taken to the perforated area 503C, and therefore the presser 571 will move in the opposite direction towards the detection system 590. If necessary, the presser 571 can perform several repeated movements, lifting up from the article between one movement and the next to avoid moving it in the wrong direction. Once the desired position has been reached with the end of the article over the perforated area 503C, suction can be activated to hold the article in position during the subsequent forward movement of the conveyor 503.

The first member found in the station 600 is a stretching device 601 (FIG. 33). The stretching device 601 is supported by a plate 603 rotating about a vertical axis X by means of a belt 605 controlled by a motor 607. The motor 607, and the support of the rotating plate 603, are supported by the fixed structure 565 of the device. Located between the plates 603 and the stretching device 601 is a piston-cylinder actuator 609 which provides said stretching device with a lifting and lowering movement according to f601. This stretching device cooperates with a suction system, not shown, located in the intermediate area between the upper branch and the lower branch of the conveyor 503, which sucks through the apertures, slots or the like indicated with 503C. Each individual article which is positioned with the end thereof at the stretching device 601 can thus be opened by lowering the member 601, engaging a side of the corresponding end of the article with this member 601, while the opposed side of material is held on the conveyor 503 by suction. The device 601 can be oriented about a vertical axis making it possible to also correctly handle “low cut” socks.

Also fixed to the structure 565 in station 600 are the mechanisms and the devices forming the two pick-up members which are activated alternatively according to the orientation of the tubular article, to always engage the same end of the tubular article with one or other of said pick-up members. When this is, for example, a sock, the pick-up member which is correctly positioned to engage the elastic edge of said sock, forming the end previously stretched or opened by the stretching device 601, is activated. As the stretching device is disposed between the two pick-up members, it forms a common stretching device or member to cooperate alternatively with one or with the other of the two pick-up members. The opening of the edge will be oriented towards one or the other of the two sides of the conveyor 503 according to the orientation with which the article was delivered from the suction duct 7 (toe or edge facing forward).

The mechanical elements which form the first and the second pick-up member, and the relative actuators are shown in their movements in FIGS. 34 to 42. where the other mechanical members of the device 501, not pertinent to operation of the pick-up members, have been omitted.

In the station 600 a motor 611 is constrained to the fixed structure 565, which motor by means of a belt 613 supplies the movement to a splined bar 615, on which pulleys 617 are coupled. These pulleys are torsionally engaged with the splined bar 615 but can slide longitudinally along the axis thereof. The pulleys 617 supply the motion to respective belts 619, entrained around the pulleys 617 and also around further idle pulleys 621. The pulleys 621 are supported by slides 623 guided along a guide 624 integral with the load-bearing structure 565 and extending parallel to the splined bar 615.

The slides 623 can slide according to the double arrow f623. They are also constrained by supports 625 to the drive pulleys 617 torsionally engaged with the splined bar 615. Ultimately, therefore, the two belts 619 can move towards and away from each other and also move independently from each other according to the double arrow f623 in a direction orthogonal to the direction of feed F of the articles on the conveyor 503.

The movement of the individual slides 623 is controlled, independently for each slide, by a piston-cylinder actuator 627. Each of the actuators 627 is constrained to the load-bearing structure 565. Of these actuators, 627X indicates the rod which is rigidly constrained to the respective slide 623.

Reference number 631 indicates two pick-up members of the articles, each of which is supported by a slide 633 sliding along a guide 635 rigidly constrained to the corresponding slide 623. In substance, therefore, each of the slides 623 which translates orthogonally to the direction F of feed of the articles and of the conveyor 503, respectively supports one of the two pick-up members of the articles, each indicated with 631, movable parallel to the direction of feed F. Movement of the pick-up members 631 along the guides 635 is indicated in the drawing with the double arrow f631.

Each pick-up member 631 has a pair of brackets 637, each of which pivots about a respective horizontal axis 637A. A respective arm 639A, 639B is integral with each bracket 637. The pivoting movement of the brackets 637 is controlled by a piston-cylinder actuator 641 arranged in an intermediate position between two supporting side panels. Each of the arms 639A, 639B has, at the lower end thereof, hinged about respective pivoting axes, respective fingers 643A, 643B, The pivoting movement of the fingers 643A, 643B is controlled by a respective piston-cylinder 645A, 645B.

The oscillating movement of the arms 639A, 639B, in combination with the oscillating movements of the fingers 643A, 643B allows, as will be explained hereunder, insertion of the fingers 643A, 643B of one pair into the open end of a tubular article and subsequent engaging by said fingers of the end of said article. The moving apart motion the fingers of each pair causes transverse stretching of the ends of the tubular article.

A bracket 651 supporting a piston-cylinder actuator 653 is rigidly connected to each slide 633 supporting each pick-up member 631. The piston cylinder actuator 653 controls the oscillating movement according to double arrow f655 about a horizontal axis of a unit 655 which supports the tubular article engaged by one or other of the pick-up members 631. More specifically, the unit 655 constrained to one slide 633 cooperates with the unit 631 constrained to the opposite slide 633, as will be more apparent from the description of a complete operating cycle of the device.

The unit 655 has at the end thereof a gripper member 657, the function of which is to hold the tubular article in an intermediate area between the two ends to prevent it from interfering with other mechanical members when, by means of the pick-up member 631 which engages the first end thereof, said article is transferred e.g. to a pair of jaws 201 of subsequent manipulator members, for example to insert each tubular article onto a transport tube or the like. The jaws 201 are represented only schematically and separately from the rest in the figures described herein, and can be substantially the same as and have the same functions as the jaws 201 described with reference to FIGS. 1 to 20.

Having described the principal member of the device, the complete operating cycle thereof will now be described with reference to the sequence in FIGS. 43A-43Q.

FIG. 43A shows a schematic longitudinal section of the spreading system and of the pick-up mechanism 525 when they are coupled to one another. The tubular article M, such as a stocking or sock, is sucked by the duct 7 through the connector 7B inside the compartment 513 with rectangular section. Suction takes place through the tubular connector 543 and the suction box 543A and then through the aperture 541 and the grid 545, as the connector 543 is connected with the suction mouth 521 and with the suction duct 523. Due to suction, the article M moves forward according to the arrow fM until knocking against the grid 545 (FIG. 43B). Here it is engaged by the retaining tooth or pawl 547 (FIG. 43B). In the example shown the article M has entered the suction duct 7 and then the spreading system 510 with the elastic edge B facing forward and the toe P backward. This orientation is entirely random and depends on how the article has been picked up from the container 1.

To spread the article M, at this point suction in the duct 7 is reversed and the article is sucked into the duct again. If by error two articles enter the compartment 513 simultaneously, one of them is unloaded back into the container 1, as the retaining pawl 547 is dimensioned so that it is unable to retain two articles M. FIG. 43C shows the article M extended towards the duct 7 but held by the pawl 547. To perform flattening and spreading of the article M, at this point the shutter element 515A is taken to the closed position thereof, in which it defines a narrow and elongated section of passage. At the same time the presser 551 is lowered for improved retention of the article M (FIG. 43D). The retaining mechanism 525 is moved away (arrow f525, FIG. 43E) pulling the article M out of the constricted cross section defined by the shutter element 515A. In this phase suction can be activated through the duct 7 which stretches the article towards the inside of said duct. The effect of this operation is to spread the article not only longitudinally, but also, and above all, transversely, thanks to the narrow and elongated shape of the cross section of passage defined by the shutter element 515A.

A similar process takes place for the opposite end (in this case the edge B) of the article in the station 509, as schematically illustrated in FIG. 43F, after the article has moved forward by one step according to the direction of the arrow F along the conveyor 503.

In the station 570 (FIG. 43G) the tubular article M is engaged by the presser 571, which for this purpose is lowered (FIGS. 43G-43H), and then translated under the detection system 590 (FIG. 431). The latter recognizes which of the two ends is facing the detection system, the elastic edge B in the example shown. The object of the subsequent operations is to ultimately take the article M with the elastic edge B thereof inserted over the pair of jaws 201. For this purpose, in the first place this end (elastic edge B) must be positioned at the level of the holes 503C, and this is again performed by the presser 571 which moves from left to right (in the drawing) to take the position in FIG. 43J). The profiles 581A, 581B center the article correctly with respect to the suction area formed by the holes 503C, positioned under which is a suction mouth, indicated schematically at 504 in FIGS. 43J-43O. Suction starts in this phase, so that subsequent feed from the station 570 to the station 600 takes place without relative movements between the edge B of the article M and the conveyor 503.

In FIG. 43K the article M is positioned with the edge B under the stretching device 601, which is lowered to engage the side of the edge B opposite the side which is held by suction on the conveyor 503. Subsequently, (FIG. 43L) the stretching device 601 is raised to stretch the edge and the fingers 643A, 643B of one of the two pick-up members 631 are inserted into said edge. In the example shown the pick-up member 631 on the left (in the drawing) is activated. If the article M had been oriented in the opposite direction, the pick-up member on the right (in the drawing) would have been activated due to the different orientation of the opening of the edge B.

FIG. 43M shows how the fingers 643A, 643B have been inserted in the edge B and are subsequently (FIG. 43N) respectively opened to horizontally stretch the edge, which is released both by the suction holes 503C, and by the stretching device 601.

To facilitate the subsequent operations of loading onto the jaw 201, the article M is engaged in an intermediate point of the longitudinal extension thereof by the gripper member 657 which is on the right (in the drawing). If the article M had been oriented in the opposite direction, the opposed gripper member 657 would have been activated.

Finally, the fingers 643A, 643B are made to pivot from the horizontal position to the vertical position (FIGS. 43O-43P) and the pick-up member 631 supporting them is made to translate according to the arrow f631 (FIG. 43Q) to position the edge B of the article M over the jaws 201. A subsequent lowering movement allows the edge B to be inserted onto the jaws 201. Subsequent handling operations can include loading onto a transport tube, as already described with reference to the embodiment in FIGS. 1 to 20.

It is understood that the drawing only shows an example provided as a practical embodiment of the invention, which may vary in forms and arrangements without however departing from the scope of the concept on which the invention is based. Any reference numbers in the appended claimed are provided to facilitate reading of the claims with reference to the description and to the drawing, and do not limit the scope of protection represented by the claims. 

1. A device for handling tubular knitted articles having a first end and a second end, the device comprising: a first pick-up member and a second pick-up member for said tubular articles, which can be actuated alternatively to engage one end of the tubular articles; detection means to determine the orientation of the first and of the second end of the tubular article, said first pick-up member and second pickup member being controlled and actuated selectively according to the orientation of the tubular article detected by said detection means, to engage always the first end of the tubular article.
 2. Device as claimed in claim 1, wherein said pick-up members are arranged and designed to engage each tubular article at the level of the first end of the tubular article.
 3. Device as claimed in claim 1, wherein said first end is an open band and said second end is a toe of the tubular knitted article, said tubular knitted article preferably being a sock or a stocking.
 4. Device as claimed in claim 1, further comprising an intermediate station, in which said tubular articles are positioned in a substantially spread position, with the first end and the second end approximately aligned with each other according to the longitudinal extension of the tubular article, said first and said second pick-up member being associated with said intermediate station, said detection means being arranged and designed to determine the orientation of the first and of the second end of the tubular article when it is in said intermediate station, said detection means being arranged and designed to detect whether said first end of the tubular article located in the intermediate station is positioned in proximity to the first pick-up member or of the second pick-up member and wherein said pick-up members are controlled so that the tubular article is engaged at its first end by the first or second pick-up member at the level of which said first end is positioned. 5-6. (canceled)
 7. Device as claimed in claim 1, further comprising a spreading system to longitudinally spread said tubular articles and longitudinally align the first end and the second end of the article, said spreading system having two longitudinal ends, said spreading system comprising two stations, each of which includes a spreading element with a shaped section of passage, through which at least a portion of the tubular knitted article is made to pass to cause flattening thereof, each station further including a pulling member of the articles, each of said spreading elements being connected to a suction duct to pull the tubular article when it is fed through said shaped section of passage. 8-9. (canceled)
 10. Device as claimed in claim 1, wherein each of said pick-up members comprises at least a pair of fingers which can be inserted into the corresponding end of the tubular article.
 11. Device as claimed in claim 1, wherein a common stretching device is associated with said two pick-up members, to stretch the end of the tubular article inside which said pick-up members are to be inserted, said common stretching device having a pair of opposed engaging members designed and controlled to engage and move away from each other opposed sides of textile material forming a corresponding end of the tubular article, to open said end, said common stretching device being arranged in an intermediate position between stand-by positions of said two pick-up members, said two pick-up members moving to transfer the tubular article to manipulator members, said manipulator members being designed and controlled to transfer each tubular article onto a transport tube, said further handling members are designed and arranged to position each tubular article on a tubular transport member, said handling members include a gripper which receives the tubular articles from one or other of said transfer devices. 12-15. (canceled)
 16. Device as claimed in claim 1, wherein a respective transfer device is associated with each pick-up member, arranged and designed to transfer a tubular article engaged by the respective pick-up member towards further handling members, each of said transfer devices including a stretching member designed and arranged to be inserted into the open end of the tubular article. 17-19. (canceled)
 20. Device as claimed in claim 1, wherein said detection means, include optical means, said detection means including at least one camera.
 21. (canceled)
 22. Device as claimed in claim 1, further comprising a conveyor which transfers the individual tubular articles from an area in which said articles are spread longitudinally, towards a station comprising said first pick-up member and said second pick-up member, wherein a common stretching device is positioned in said station comprising said first pick-up member and said second pick-up member, said detection means being arranged the path of said conveyor, wherein a translation device is associated with said detection means, which translates each tubular article orthogonally to the direction of feed of said conveyor, to move an end of each tubular article to said detection means, said conveyor being formed of a continuous member, moving in a direction substantially orthogonal to the orientation of said tubular articles. 23-26. (canceled)
 27. Method for handling tubular articles with a first end and second end, the method comprising the steps of: picking up a tubular article from a container, in which said articles are arranged randomly; transferring said article to an operating position, with its ends approximately aligned according to a direction of longitudinal extension of the tubular article; recognizing which of the two ends of said article is the first end; after recognizing the first end, selectively engaging the tubular article at said first end and moving it away from said operating position.
 28. Method as claimed in claim 27, further comprising the steps of: arranging in said operating position a first pick-up member and a second pick-up member; controlling said first pick-up member and said second pick-up member to actuate either said first pick-up member or second pick-up member, in proximity to which said first end of the tubular article is arranged, to engage said first end of the tubular article, wherein said first end is engaged and opened by a stretching device common to said first and second pick-up members and engaged selectively by one or other of said first and second pick-up members, according to the orientation of the first and of the second end, said tubular article being transferred from the pick-up member that engaged said first end onto further manipulator members.
 29. (canceled)
 30. Method as claimed in claim 27, wherein: the first end of the tubular article is engaged by a transfer device; a first and a second transfer device are associated with said first and second pick-up member, wherein the tubular article is inserted with its first end facing forward over a tubular member, said first end of the tubular article being engaged and opened by the respective pick-up member. 31-32. (canceled)
 33. Method as claimed in claim 27, wherein said first end is engaged and opened by a stretching device. 34-35. (canceled)
 36. Method as claimed in claim 27, wherein said tubular article is spread longitudinally, said article being spread with the first and the second end approximately aligned longitudinally with each other and wherein when the article has been spread detection takes place to identify which of the two ends of the article is the first end, said first end is an open band and said second end is a toe of the tubular knitted article, said tubular knitted article being a sock or stocking. 37-38. (canceled)
 39. A device for handling tubular knitted articles having a first end and a second end, the device comprising: an operating position; associated with said operating position, a first pick-up member and a second pick-up member for said tubular articles, which can be actuated alternatively and selectively to always engage the first end of the tubular articles.
 40. Device as claimed in claim 39, further comprising: detection means to determine the orientation of the first and of the second end of the tubular article, said first pick-up member and said second pick-up member being controlled to engage the tubular article alternatively, according to the orientation of the tubular article detected by said detection means, so that each tubular article is engaged always at the first end notwithstanding its orientation in the operating position; a control unit, programmed to receive information from said detection means and to control actuation of one or other of said first pick-up member and of said second pick-up member according to the information received from said detection means, said detection means being arranged and designed to determine the orientation of the tubular article when it is in said operating position. 41-42. (canceled)
 43. Device as claimed in claim 39, wherein a common stretching device is associated with said first pick-up member and said second pick-up member, to stretch the end of the tubular article into which said pick-up members must be inserted, said common stretching device having a pair of opposed engaging members designed and controlled to engage and move way from each other opposed sides of textile material forming a corresponding end of the tubular article, to open said end, said common stretching device being arranged in an intermediate position between stand-by positions of said two pick-up members, said two pick-up members moving to transfer the tubular article to manipulator members, said manipulator members being produced and controlled to transfer each tubular article onto a transport tube, said pick-up members and/or said stretching device being oriented angularly to engage the first end of tubular articles in which said first end has an opening inclined variably with respect to a principal direction of longitudinal extension of the tubular article, said first pick-up member and said second pick-up member being controlled to be activated selectively and always engage the first of said ends of the tubular articles, notwithstanding the orientation of said tubular articles in said operating position. 44-49. (canceled)
 50. Method for handling tubular articles with a first end and second end, the method comprising the steps of: arranging individual tubular articles sequentially in an operating position; detecting which end is the first end; engaging each tubular article selectively at said first end and moving it away from said operating position.
 51. Method as claimed in claim 50, further comprising the steps of: arranging in said first operating position a first pick-up member and a second pick-up member; engaging each tubular article alternatively with said first pick-up member or with said second pick-up member according to the position of said first and second end.
 52. Method as claimed in claim 51, further comprising the steps of: recognizing the position of the first end of an article in the operating position; and actuating one or other of said first and second pick-up members always to engage the first end of the tubular article, wherein said first end is opened with a common stretching device and is subsequently engaged selectively with said first or said second pick-up member.
 53. (canceled)
 54. Method as claimed in claim 50, wherein the pick-up member which engaged said first end transfers said tubular article to a further manipulator device.
 55. Device as claimed in claim 2, wherein said first end is an open band and said second end is a toe of the tubular knitted article, said tubular knitted article preferably being a sock or a stocking.
 56. Device as claimed in claim 2, further comprising an intermediate station, in which said tubular articles are positioned in a substantially spread position, with the first end and the second end approximately aligned with each other according to the longitudinal extension of the tubular article, said first and said second pick-up member being associated with said intermediate station.
 57. Method as claimed in claim 28, wherein the first end of the tubular article is engaged by a transfer device. 